The elements complement each other, fight and make alliances. Earth needs water, so Earth signs get on swimmingly with Water signs. Air dries the land, so Air and Earth signs have difficulty getting on and appreciating each other. Fire puts out water, hence why Water signs struggle to deal with Fire signs' sensitivity, emotion, brilliance and pride.

Despite the way the elements interact, there are exceptions to these rules. Note that twin signs, Aries and Aries and Taurus and Taurus maybe just know each other too well. They may experience a lack of chemistry and attraction (opposites attract and all that).